Causality Based Propagation History Ranking in Social Networks

In social network sites (SNS), propagation histories which record the information diffusion process can be used to explain to users what happened in their networks. However, these histories easily grow in size and complexity, limiting their intuitive understanding by users. To reduce this information overload, in this paper, we present the problem of propagation history ranking. The goal is to rank participant edges/nodes by their contribution to the diffusion. Firstly, we discuss and adapt Difference of Causal Effects (DCE) as the ranking criterion. Then, to avoid the complex calculation of DCE, we propose a "resp-cap" ranking strategy by adopting two indicators. The first is responsibility which captures the necessary face of causal effects. We further give an approximate algorithm for this indicator. The second is capability which is defined to capture the sufficient face of causal effects. Finally, promising experimental results are presented to verify the feasibility of our method.